Generally, it is known to provide a cargo bed with a floor for a vehicle, such as a pick-up truck. The cargo bed together with side walls and the floor can define a cargo carrying area. It is also generally known to provide external storage boxes that can be mounted within the cargo bed, typically adjacent to a cab of the pick-up truck. Such external storage boxes typically span the width of the cargo bed and are accessible from within the cargo bed of the vehicle. One disadvantage of such external storage boxes is that they are not easily accessible from outside of the cargo bed or cargo carrying area. Another disadvantage of such external storage boxes is that they are fastened or mounted to the vehicle such that they are not removable or portable. Yet another disadvantage of such external storage boxes is that they reduce a size of the cargo carrying area and do not allow full use of the cargo bed. Thus, there remains a need in the relevant art for a removable storage device that overcomes the aforementioned and other disadvantages.